摘要
盐胀是硫酸盐渍土的主要危害,硫酸盐渍土机场地基处理的关键在于减少盐胀。通过不同荷载作用下的盐胀试验,研究了荷载对不同压实度、不同含盐量的硫酸盐渍土盐胀的抑制效果,拟合了盐胀经验公式,探讨了换填覆重法硫酸盐渍土机场地基处理。压实度不宜太高,在满足道面承载力的条件下建议在90%～95%之间取值;道面2m以下可以填弱盐渍土,建议含盐量不要超过0.5%;水分危险点危害最大,必须重视排水设计。给出了确定换填覆重法最小荷载及最小厚度的方法。计算表明,覆重荷载50kPa基本能抑制含盐量小于0.5%的硫酸盐渍土的盐胀,采用砂砾石材料最小覆重层厚度约2m。换填覆重法在西北地区硫酸盐渍土机场地基处理中具有较好的应用前景。
Salt heaving is the main disease of sulphate saline soil; and the key point of ground treatment for airport engineering is to eliminate salt heaving. Experiments about salt heaving under different loads were carried out to study the restraining effect of load on sulphate saline soil with different compaction degrees and saltnesses; and salt heaving formula which can calculate salt heaving rate was deduced. Control guideline of ground treatment by heavy cover replacement technique was discussed： compaction degree shouldn＇t be too high, the suggested value can be picked from 90% to 95% when ground carrying capacity is adequate; feeble sulphate saline soil can be used for filling 2 meters below pavement, the suggested saltness is lower than 0.5%; water dangerous point produces the worst danger, so drainage design should be taken into consideration seriously. The method and flow chart for calculating the least load and the least thickness was given. Calculation indicates that 50 kPa is almost enough to control salt heaving; the least thickness is about 2 meters with grit stone for cover. Heavy cover replacement technique will be used widely in ground treatment in airport engineering with sulphate saline soil in Northwest China.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2010年第12期3880-3886,共7页
Rock and Soil Mechanics
关键词
地基处理
换填覆重法
危险点:硫酸盐渍土
盐胀
机场
ground treatment
heavy cover replacement technique
dangerous point
sulphate saline soil
salt heaving
airport
